Occupant-controlled



-Ma'rch 31, 1964 w. GREUB 3,127,188

OCCUPANT-CONTROLLED, DESTRUCTION-CLIMBING WHEEL CHAIR Filed April 23, 1962 4 Sheets-Sheet 1 w. GREUB.

March 31, 1964 OCCUPANT-CONTROLLED, OBSTRUCTION-CLIMBING WHEEL CHAIR Filed April 23, 1962 4 Sheets-Sheet 2 [3d 736 I30 62 74C 2.? 25 27 30 76' 7/0 740 22 W. GREUB March 31, 1964 Filed April 25, 1962 4 Sheets-Sheet 3 .3 n d h 8 mm M Q m M vii. Lu kw 8 Rm 7 MM a m I hm Q uh G Q N .1 I1 I 1 l l 1! a. x m mm m 1 iilfii I! W IMM s w a March 31, 1964 w. GREUB 3,127,188

OCCUPANT-CONTROLLED, OBSTRUCTIONCLIMBING WHEEL CHAIR Filed April 23, 1962 4 Sheets-Sheet 4 United States Patent 3,127,188 OCCUPANT-CONTROLLED, OBSTRUCTION- CLIMBING WHEEL CHAIR Werner Greub, Rauracherstrasse 11,

Riehen, Basel, Switzerland Filed Apr. 23,1962, Ser. No. 189,616 Claims priority, application Switzerland Apr. 23, 1961 6 Claims. (Cl. 2805.22)

This invention relates to an improved wheel chair adapted to move over obstructions and more particularly to climb stairs.

The object of the invention is to provide an improved wheel chair of this character, the operation of which is controlled by the occupant of the wheel-chair and aifording perfect safety in every situation of normal use.

A further object is to provide an improved construction of stair-climbing chair which can be propelled by the occupant even on stair-climbing. 7

Other objects and advantages will become apparent as the description proceeds and when considered in conjunction with the accompanying drawings in which:

FIG. 1 is a somewhat diagrammatic perspective view of an invalid chair embodying the invention and shown in the position after climbing a stair or ready for descending a stair,

FIG. 2 is. an elevational view of a portion indicated by arrow II of FIG. 1, and partly in section along line IIII of FIG. 3, to an enlarged scale,

'FIG. 3 is a sectional view taken along the III-III of FIG. 2,

FIG. 4 is a sectional view taken along line IVIV of FIG. 1 and shows gearing means; and

FIGS. 5 to 17 are diagrammatic views illustrating several states of use of the wheel chair represented in FIGS. 1 to 4.

The wheel-chair represented in the drawings comprises two identical side frames generally denoted with 1, each such frame being a rigid welded construction made up of tubes 2, 3, 4, 5, 6 the configuration and arrangement of which can easily be recognized from FIG. 1. Linking means interconnect the two frames 1 either in a rigid manner or in such a manner that these frames any be put closely one against the other, with corresponding frame tubes extending parallelly; these linking means are not shown for the sake of clarity and because they are well known in the art. Web strips 7, 8, 9 which in the position of use of the two frames I extend in a stretched condition between them constitute a back rest, a seat and a leg rest, respectively. There is also a foldable or retractable stifi foot rest 10.

Disposed on the exterior sides of the two chair frames, and secured to them in a manner described more fully below, there are two quite identical units which may be operated and controlled independently from each other by the occupant of the chair either to drive on even ground or on floors or to move over obstructions of various kinds (see FIGS. 5 to 17 described more below).

Each such unit comprises a support 11 rigidly secured to the rear end of the tube 5 of the adjacent chair frame 1, an axle 12 rotatably mounted in a pair of downwardly and rearwardly extending, forked legs 11a of support 11, two casings 13, .14 tiltably mounted on bushings 15, 32 supported on the end portions of axle 12, a double belt drive pulley 16 located between the legs 11a of support 11 and rotatably mounted on axle 12, casing 13 extending forwardly and more or less downwardly while casing 14 is tiltable firom a position in which it extends substantially parallelly to the chair back (FIG. 5) to a position in which it extends rearwardly substantially at right angles to the chair back (FIG. 6). A pulley 17 is loosely mounted on an axle 18 supported on the free Patented Mar. 31, 1964 (fore) end of casing 13 and an endless belt 19 extends around the pulleys 16, 17. Two pulleys similar to pulley 17 are respectively mounted on axles 20, 21 supported on the free (rear) end of casing 14 in a disposition that can be seen from FIG. 1 and an endless belt 22 extends around these two pulleys and around pulley 16.

The pulley 16 is shown to be mounted on axle 12 by means of two circular rows of balls 23, 24 and of two annuli 25, 26 screwably adjustable on axle 12 and lockable on this axle by means of a thin nut 27 and 28, respectively. The axles 18, 20, 21 support the corresponding pulleys in similar manner. Means may optionally be provided for adjusting the axles 1S and 2t lengthwise of the casings 13, 14 to stretch the belts 19, 22 to the whole exterior surface of which is bonded a strip 29 of softer rubber or other appropriate anti-glide material. Nuts 30, 3-1 are screwed on the end portions of axles 12 against the bushings 15, 32 which bear against the nuts 27, 28. The lower track of each of the belts 19, 22 is supported e.g. by a strip of antifriction material 19 (such as Teflon) secured to the lower portions of the side walls of the corresponding casing 13 or 14 and is also laterally guided by downwardly extending flanges 20" thus defined of the respective casing.

Each of the afore-mentioned units also comprises a conventional wheel generally denoted with 33, the rim of which is provided with and rigidly connected to a pneumatic concentric, laterally oiiset circle 34 of smaller diameter; such circle is acted upon by the occupant of the chair for propelling purposes, but not only in the usual manner with the wheels 33 hearing on the ground, but also, as will be explained in detail below, for driving the endless belts 19, 22 every time when the wheel chair should move over an obstruction. Each of the two units also comprises means for raising and lowering the appurtenant wheel relatively to the adjacent frame 1, further means for changing the relative angular position of the casings 13, 14 and means permitting to tilt the frame 1 about the axle 12 with regard to the two casings 13, 14 while same are locked to each other in any one of several positions; these three means may be operated independently of one another by the occupant of the chair and the three means of one unit are independent of the corresponding means of the other unit.

On each unit the hub 35 of the wheel 33 is rotatably and axially fixedly mounted in conventional manner on an axle 35' secured with one of its ends to the free end of a crank arm 36 (FIGS. 1 and 4) the other end of which is secured at 37' to a crank axle 37. This axle 37 is rotatably and axially fixedly mounted in a bearing block 38 to which are hinged a clamp 39 and a screw 40 with a nut 41 by means of which elements the block 38 is immovably secured to a lower portion of the tube 2 of the adjacent frame 1. A Worm gear 42 is made integral with the crank axle 37 and meshes with a worm 43 provided on a shaft 44 journaled in block 38; this shaft extends upwardly and is provided with a handle 45 operable by the occupant of the chair. It is easy to understand that the elements 36, 37, 43, 44, 45 are components of the means for lowering and raising the wheel 33 as shown also in FIGS. 7 and 14. The worm gearing 42, 43 is self-locking to prevent any undesired angular movement of the crank arm 36 that supports the wheel 33.

A permanent driving connection (FIG. 4) is provided between the wheel 33 and the belts 19 and 22, acting in every postion of the just described wheel lowering and raising means and also in every angular position of the casing 13 and 14. This driving connection includes a chain gear 46 secured to the hub 35 of the wheel 33, a chain 47, a chain gear 48, a worm 49 journaled in a casinglike extension 36a of crank arm 36, a worm gear 50 also journaled in this extension 36a, meshing with the worm (A) 49 and secured to a bevel gear 51, a bevel gear 52, in mesh with 51, a trunnion 53 journaled in the extension 36a, a spur gear 54 rigidly connected to the bevel gear 52 by the trunnion 53, a member 55 loosely mounted on the crank axle 37 and including a spur gear 55 in mesh with 54, and a chain wheel 56, a chain 57 and a chain wheel 58 (FIGS. 2 and 3) secured to the double belt pulley 16. An important feature consists in that the worm gearing d9, 50 is of the self-locking type, with the result that movement of the belts 19, 22 in either direction may only occur if the wheel 33 is rotated, whilst a reverse drive of the wheel 43 by the belts 19, 22, e.g. during climbing or descending a stair, is impeded. Assuming that a notable slip of the belts 19, 22 on the double pulley 16 does never occur, I have thus provided a foolproof safety device and furthermore an invalid occupying the wheel chair, on climbing stairs, is able to propel the chair slowly upward by acting on the rings 34 of the wheels 33 without too much eifort, owing to the convenient reduction ratio provided in the whole driving connection by the presence of this worm gearing 49, 50.

I will now describe in detail, more particularly with reference to FIGS. 1 to 3, the means for varying the relative angular position of the casings 13, 1 1 with respect to each other and the means for varying the angular position of the frames 1 with respect to these casings. It should be kept in mind that each frame 1 and the two casings 13, 14 of the adjacent unit has a common tilting axis, namely the axis of the corresponding axle 12. This axis is also the axis of rotation of a first hand lever 59 mounted on the bushing 15 at the inside of one of the two legs 14a, 14b of the casing 14-, and provided at its outer end with a curved sleeve 59a capable of sliding on the tube 6 of frame 1. This tube 6 extends along an arc of circle having its center on the axis of the axle 12; it has a plurality of notches 6a one of which is normally engaged by a locking bolt 66 guided in a handle 61 secured to one end of the sleeve 59a; the locking bolt 66 may be disengaged from any one of the notches 6a by action of the thumb of the hand holding the handle 61, against the resistance of a spring, to allow angular motion of the first hand lever 59. A swivel 62 secured to a portion of this lever 59 located between the legs 13a, 13b of casing 13 loosely mounts a toothed disc 63 which is permanently in mesh with an external toothing 140 of the adjacent leg 14a of casing 14 and also with an internal toothing 13c of a plate 13d welded to the leg 13a of casing 13. The toothings 13c, 140 have their common center on the axis of axle 12 and the radius of toothing 140 is half of that of the toothing 130. A second hand lever 64 is integral with, or welded to, the casing 13; its outer end portion extends through a long slit 65 (FIG. 1) of an arcuate bar welded to the sleeve 59a and is provided with a handle 66 guiding a locking bolt 67; the latter normally engages one of a plurality of notches provided on one side of the slit 65 and may be depressed to allow for an angular motion of the second hand lever 6 bodily with the casing 13 with respect to the first hand lever 59.

If such angular motion is carried out for example in the counterclockwise direction as seen in FIG. 2, the toothed disc 63 is rotated in the counterclockwise direction about the swivel 62 and thereby the casing 14 is obviously rotated in the clockwise direction owing to the meshing of disc 63 with the toothing 140 of the leg 14a of this casing 14. Since the radii of the toothings 13c, 140 are 2:1, the angle of tilting of casing 1 is twice the angle of tilting of the casing 13 with the use of second hand lever 64. This explains how the two casings 13, 14 may be put in the several angular positions relative to each other, as appears from comparison of some of the FIGS. 5 to 16 with one another.

If the occupant of the wheel chair depresses the locking bolts 66 on both units, he can then vary the inclination of the chair proper (i.e. of the frames 1, webs 7,

8, 9 and foot rest 10) while the hand levers 59, 64 (and thus also the casings 13, 14) remain locked to each other in fixed angular position. For such variation of inclination pursuant to a depression of the locking bolts 60 the occupant well seated on the chair has merely to flex more or less his elbows. No excessive effort is needed because in every case in which he effects such variation (see FIGS. 8 and 13) the center of gravity of occupant and chair proper is located pretty near to the vertical plane containing the common axis of the axles 12 of the two units.

Having now described the structure and the details of the different actions that may be performed, it is easy to understand the sequence of diagrammatic pictures, from FIGS. 5 to 15, which depict the mode of use of the wheel chair when descending a stair (or in reverse sequence, from FIG. 15 to FIG. 5, when climbing a stair).

FIG. 5 depicts the state of the several components for motion on substantially flat ground or floors. The wheels 33 and a conventional ground engaging wheel 68 supported on a bracket 69 secured for example to the foot rest 10 are lowered and serve as usual.

FIGS. 6 to 8: Before descending a stair, the occupant first lowers the casings 13, 14 with the endless belts 19,

22 (only the latter ones are shown, for the sake of clarity) by actuation of the second hand levers 64 (FIG. 6). Thereafter the occupant operates the handles 45 to raise the wheels 33 (FIG. 7). By acting on the first hand levers 59 the occupant then tilts rearward the chair proper, to adapt his position to the slope of the stair (FIG. 8). FIG. 9: The occupant may now act on the wheels 33 so that the force belts 19 pass over the upper edge of the stair, until the double pulleys 16 are located over this edge. 7 FIG. 10: Vt hen this position is attained, the occupant actuates the second hand levers 64 to bring the lower tracks of the belts 19, 22 in line with each other. If this implies an angular motion of for example 30 of the casings 13, 14 relative to each other, he has to retract the levers 64 by 10; the casings 14 will be tilted by the remaining 20. It will be appreciated that this most delicate transition stage in the descending of a stair goes on without shock and with the occupant always in a comfortable, safe position. The front belts 19 are always prevented from moving in uncontrolled manner, owing to the self-locking worm gearing 49, 50. The same holds true for the actual descending stage during which the movable components occupy the relative positions shown in FIG. 11.

FIG. 12 shows that when the pulleys 17 reach the bottom of a stair, the second hand levers 64 should be somewhat displaced in the same directions as in the position of FIG. 10, to prepare for the transition to position of FIG. 13, in which the first hand levers 59 are operated in order to tilt the chair proper forwardly into its normal position.

In the position of FIG. 14 the occupant operates the handles 45 in order to lower the wheels 33 until the same engage the even floor or ground.

In the position of FIG. 15 the occupant retracts the second hand levers 64 to put the belts 19, 22 into their initial position shown in FIG. 5.

The positions of the components as shown in FIG. 1 are the same as in FIG. 6.

FIG. 16: If a winding stair should he climbed or descended, the mode of use is not substantially different from that just described, but in the stage of FIG. 8 the first hand levers 59 of the two units should be positioned somewhat differently or, alternatively, the adjustment of these levers 59 (and consequent that of the belts of one of the two units) may be corrected when the stage shown- FIG. 17 shows the positions of the belts 19, 22 used to move over small steps as those of causeways, sidewalks, footways and the like.

Many modifications may be made in the embodiment shown and described by way of example. A secondary frame structure including the arcuate tube 6 and sections of tube rigidly connecting this tube with the support 11 and the block 38 may be removably clamped to each of the frames 1 or similar structures of the chair proper, whereby the two units may be removed for stowing in the interior of standard automobile or taxi cab.

With such self-contained units it will also be easy to convert an orthodox wheel chair into stair climbing wheel chair according to the invention.

I claim:

1. An occupant-controlled, obstruction-climbing wheel chair, comprising a chair framing and on both sides of this chair framing: support means rigidly connected to a bottom rear portion of said chair framing, axle means rotatably mounted on this support means, a first rigid member and a second rigid member pivotally mounted on said axle means, means for adjusting the relative angular position of said two rigid members with regard to each other and with regard to the chair framing, a first and a second endless track means movably mounted respectively on said first and said second rigid member and means for driving said first and second endless track means, said means for adjusting the relative angular positions of said two rigid members being capable of adjustment from a position wherein the lower sides of the first and second track means enclose a downwardly open obtuse angle to a position in which said lower sides are located substantially in the same plane.

2. An occupant-controlled, obstruction-climbing wheel chair, according to claim 1, in which said means for driving the first and second track means include a member rotatably mounted on said axle means.

3. An occupant-controlled, obstruction-climbing wheel chair, according to claim 2, in which each of said first and second track means is constituted by an endless belt.

4. An occupant-controlled, obstruction-climbing wheel chair, comprising a chair framing and on both sides of this chair framing: support means rigidly connected to a bottom rear portion of said chair framing, axle means rotatably mounted on this support means, a first rigid member and a second rigid member pivotally mounted on said axle means, means for adjusting the relative angular position of said two rigid members with regard to each other and with regard to the chair framing, a. first and a second endless track means movably mounted respectively on said first and said second rigid member, and means for driving said first and second endless track means, said adjusting means including a first hand lever pivotally mounted on said axle means and capable of being locked to the chair framing in several angular positions, a swivel secured to this first hand lever at the proximity of said axle means and parallel thereto, a toothed disc rotatably mounted on said swivel, a second hand lever rigidly secured to said first rigid member and being capable of being locked to said first hand lever in several relative positions, an internal toothing on said first rigid member and an external toothing on said second rigid member, both said internal and external toothings being in permanent mesh with said toothed disc.

5. An occupant-controlled, obstruction-climbing wheel chair, comprising a chair framing and on both sides of this chair framing: support means rigidly connected to a bottom rear portion of said chair framing, axle means rotatably mounted on this support means, a first rigid member and a second rigid member pivotally mounted on said axle means, means for adjusting the relative angular position of said two rigid members with regard to each other and with regard to the chair framing, a first and a second endless track means movably mounted respectively on said first and second rigid member, and means for driving sm'd first and second endless track means, wherein said means for driving the first and second track means includes a member rotatably mounted on said axle means, a block on each side of the chair framing rigidly connected to said framing, a crank mounted in this block to be rotatable about an axis parallel to said axle means and having at its free end a crank pin also parallel to said axle means, a chair wheel rotatably mounted on said crank pin, means rotatably mounted on said block for rotating the crank, thereby to lower or to raise the chair wheel, and in which said driving means includes the chair wheel and a permanent driving connection from same to said References Cited in the file of this patent UNITED STATES PATENTS 2,319,008 McCormack May 11, 1943 2,751,027 McLaughlin June 19, 1956 FOREIGN PATENTS 519,508 France Jan. 16, 1921 980,237 France Dec. 20, 1950 

1. AN OCCUPANT-CONTROLLED, OBSTRUCTION-CLIMBING WHEEL CHAIR, COMPRISING A CHAIR FRAMING AND ON BOTH SIDES OF THIS CHAIR FRAMING: SUPPORT MEANS RIGIDLY CONNECTED TO A BOTTOM REAR PORTION OF SAID CHAIR FRAMING, AXLE MEANS ROTATABLY MOUNTED ON THIS SUPPORT MEANS, A FIRST RIGID MEMBER AND A SECOND RIGID MEMBER PIVOTALLY MOUNTED ON SAID AXLE MEANS, MEANS FOR ADJUSTING THE RELATIVE ANGULAR POSITION OF SAID TWO RIGID MEMBERS WITH REGARD TO EACH OTHER AND WITH REGARD TO THE CHAIR FRAMING, A FIRST AND A SECOND ENDLESS TRACK MEANS MOVABLY MOUNTED RESPECTIVELY ON SAID FIRST AND SAID SECOND RIGID MEMBER AND MEANS FOR DRIVING SAID FIRST AND SECOND ENDLESS TRACK MEANS, SAID MEANS FOR ADJUSTING THE RELATIVE ANGULAR POSITIONS OF SAID TWO RIGID MEMBERS BEING CAPABLE OF ADJUSTMENT FROM A POSITION WHEREIN THE LOWER SIDES OF THE FIRST AND SECOND TRACK MEANS ENCLOSE A DOWNWARDLY OPEN OBTUSE 